1. Field of the Invention
The invention relates generally to pixels within image sensors. More particularly, the invention relates to interconnect patterns within pixels within image sensors.
2. Description of Related Art
Semiconductor image sensors, including complementary metal oxide semiconductor (CMOS) image sensors and charge coupled device (CCD) image sensors, are gaining in popularity. In general, semiconductor image sensors are used as imaging components within various types of consumer and industrial products. Non-limiting examples of applications for image sensors include scanners, photocopiers, digital cameras and video telecommunications devices. CMOS image sensors provide advantages in comparison with other types of semiconductor image sensors insofar as CMOS image sensors are generally less expensive to fabricate. CMOS image sensors also generally consume less power.
Image sensors typically comprise an array of pixels that in turn comprises an array of photosensors located within a semiconductor substrate. The photosensors are often photodiodes. Aligned over the array of photosensors is an array of lens structures (or lens layers) that is used to capture incoming light that is representative of an object desired to be imaged. Interposed between the array of photosensors and the array of lens structures are spacer layers and color filter layers that allow for color discrimination and focusing of incoming light.
Image sensors also typically include dark pixels (i.e., pixels from which light is excluded) in addition to active pixels (i.e., pixels that are actively used within an imaging application). An electrical output from a dark pixel is typically used to determine a background response of a pixel, for purposes of electrical correction for active pixel output within the image sensor.
Pixel dimensions within image sensors are certain to continue to decrease and such decreased pixel dimensions within image sensors are likely to lead to a need for more efficient image sensor structures and methods for fabrication thereof. Included are sensors that include dark pixel correction. Thus, desirable are image sensors, and methods for fabrication thereof, that efficiently provide for dark pixel correction.